EP 1 002 744 A1 discloses a two-piece paperboard container that houses a unit dose product on an internal slide card within an outer paperboard shell. This package has two internal locks that prevent the slide card from being pulled out without triggering a lock release mechanism. This package is focused around providing a child resistant, senior-friendly unit dose package that can be opened and closed numerous times and then finally disposed of.
The paperboard shell is formed by folding a blank consisting of three major panels connected by two narrow panels. The centre major panel of the blank is adapted to form a bottom surface of the package, whereas one of the two outer major panels of the blank is adapted to form a top surface of the package. The other outer panel is adapted to form an inner top surface of the package. The inner top surface and the top surface are glued to each other.
The panel forming the inner top surface is provided with a through-going opening or cut-out. The panel forming the top surface is provided with a score line formed as an oval. The panel is cut through along this score line. The oval score line and the through-going opening are positioned on the two outer panels in such a manner that when forming a package the oval score line will be positioned on top of the through-going hole. The portion of the panel being within this oval score line may be pushed as a push-button.
The internal slide card is provided with a tab, which is formed at the leading edge (leading when the slide card is inserted into the package) and refolded backwards over the slide card. When the slide card is inserted completely inside the shell, the refolded tab will due to its spring-back properties enter into the through-going opening of the panel forming the inner top surface.
When a user pulls the slide card the tab will be forced into the through-going opening and thus block the slide card from being pulled out of the package. However, if the user pushes the push-button the tab will be pushed out of the through-going opening and the slide card may thus be pulled out of the package.
At the opening, through which the slide card is inserted into the package, the package is provided with an inwardly folded tab, which interacts with the refolded tab of the slide card to prevent the slide card from being pulled completely out of the package.
However, this package does not represent a satisfactory design. Already when a refolded tab looses only a portion of its spring-back properties (after being pushed inwardly a few times) it will not make a complete spring-back movement. The design of the package disclosed in EP 1 002 744 A1 relies on the thickness of the panel forming the inner top surface. The locking function is thus made dependent upon the selection of sufficiently thick material for the package. Consequently, already minor short-comings of the spring-back of the refolded tab will result in that the refolded tab will not enter the through-going opening and the locking function is not accomplished. Moreover, any lack of spring-back of the push-button will result in that the push-button will occupy a space in the through-going opening and thus exert a force onto the refolded tab being counterproductive to the spring-back of the refolded tab.
WO 02/38454 A1 discloses a package made of cardboard, comprising a sleeve and an insert, the sleeve being provided with at least one catch tab located on the inside of the sleeve and provided with at least one projection, so that the catch tab forms an angle with the upper wall of the sleeve. At least one locking tab is provided on the insert, which is arranged so as to be at least in part inserted between the catch tab and the upper wall. At least one operating tab is provided, in addition to which the sleeve is provided with at least one cut-out next to the operating tab, the operating tab being arranged so as to be pressed by a user against locking tab, movement of the insert in the sliding direction towards the opening being made possible. Although it has been found that this design offers a satisfactory locking function it has been proven difficult to use this design for so-called flat-laid, pre-glued distribution of a package.
WO 03/101840 A1 discloses a package comprising a sleeve of essentially parallelepipedal shape, and an insert, which can be inserted into and withdrawn from the sleeve in a sliding direction through an opening in the sleeve, the sleeve comprising four longitudinal walls, which are essentially parallel to the sliding direction. The package is characterized in that the sleeve is provided with a first stop tab which extends from a first to a second of the longitudinal walls, the tab being at least partly separated from the first longitudinal wall and the second longitudinal wall in that the insert has a first locking edge, the insert being prevented, upon contact of the first locking edge with the first stop tab, from moving out of the sleeve, and in that the first locking edge can, by elastic deformation of a part of the insert by means of manoeuvring by a user, be moved so that its movement past the first stop tab is made possible.
Although it has been found that this design offers a satisfactory locking function it has been proven difficult to use this design for so-called flat-laid, pre-glued distribution of a package.